Process for preparing ammonium salts of alkanoic acids

ABSTRACT

A FREE FLOWING PARTICULATE SOLID AMMONIUM SALT OF AN ALKANOIC ACID HAVING 1-10 CARBON ATOMS IS PREPARED BY SPRAYING THE ALKANOIC ACID INTO AN ATMOSPHERE OF AMMONIA VAPOR IN A REACTION ZONE IN A MANNER TO PREVENT THE ACID SPRAY FROM CONTACTING THE INTERNAL SURFACE OF THE REACTION ZONE.

Jan. 15, 1974 E. R. SKOV ETAL PROCESS FOR PREPARING AMMONIUM SALTS OI- ALKANOIC ACIDS Filed Nov.

United States Patent Ofiice lijbtidibb Patented Jan. 15, 1974 U.S. Cl. 260-540 15 Claims ABSTRACT OF THE DISCLOSURE A free flowing particulate solid ammonium salt of an aiitanoic acid having l-lO carbon atoms is prepared by spraying the ailtunoic acid into an atmosphere of ammonia vapor in a reaction zone in a manner to prevent the acid spray from contacting the internal surface of the reaction zone.

BACKGROUND OF THE INVENTION This invention is in the field of ammonium salts of ailtaaoic acids having l-lO carbon atoms. Said invention is a process for preparing said salts in essentially quantitative yield based on the reactants consumed. The product i\ a highly (or substantially) pure. free flowing. particulute. anhydrous solid salt having the formula RCOONH where R is hydrogen or an alkyl group having l-9 carbon lliUf'ilS.

A prior art method for preparing such salts in essentially pure anhydrous form was described by Zullanti (J. Am. Chem. Soc. i941.63.3l23-3l24).2uflantiprepared a suit by spraying a very small amount (about 0.5 cc.) of a liquid anhydrous aikanoic acid on the wall of a U-tube while passing anhydrotts ammonia vapor through the tube. Although the Zutlanti method produces ammonium salts of high purity. the product is not free flowing and it adheres to the wall of the U-tubc. The prior art method does not produce a free flowing product. and said method is not suited for commercial operation on either a batch or continuous basis.

SUMMARY OF THE INVENTION In summary, this invention is directed to an improvement in a process for preparing a solid ammonium salt of a liquid anhydrous alkunoic acid having [-10 carbon atoms per molecule comprising contacting a spray of said liquid anhydrous alltuaoic acid with anhydrous ammonia vapor in a reaction zone having an external surface and an internal surface (including a side wall) an upper portion. and a lower portion and recovering the resulting solid ammonium salt of said liquid alltanolc acid, the improvement comprising; filling the reaction zone with anhydrous ammonia vapor by vaporizing liquid anhydrous ammonia therein and spraying particles of said liquid anhydrous ulltanoie acid into the reaction zone without contact between the liquid anhydrous alitanoic acid particles and the internal surface (especially the side wall) of the reaction zone to produce a free flowing particulate solid product consisting essentially of said ammonium salt of said liquid anhydrous ailzanoic acid.

BRlEF DESCRIPTION OF THE DRAWING The drawing shows, in section with parts cut away. a preferred apparatus for conducting the process of the instant invention.

DESCRlPTlON OF PREFERRED EMBODIMENTS In preferred embodiments of the process of the above summary:

(1) The alkanoic acid has 4-5 carbon atoms. (2) The particles of liquid anhydrous alltanoic acid are of a size to produce particles of said free flowing ammonium salt of said liquid anhydrous alltanoic acid which pass a. mesh screen and the process is operated in a fully continuous manner.

(3) The liquid anhydrous alkanoic acid is isobutyric acid or valeric acid.

In another preferred embodiment ("Embodiment A") this invention is directed to an improvement in a process for preparing a solid ammonium salt of a liquid anhydrous alltanoic acid having l-lO carbon atoms per molecule comprising contacting a spray of said liquid anhydrous alitanoic acid with anhydrous ammonia vapor in a reaction zone having an external surface, an internal surface. a side wall. a top, a bottom, on upper portion, and a lower portion and recovering the resulting solid ammonium salt of said liquid alkanoic acid, the improvement comprising;

(a) filling the reaction zone with anhydrous ammonia vapor by feeding liquid anhydrous ammonia into the upper portion of the reaction zone via a spray nozzle and vaporizing said ammon a in the upper portion of said zone; and

(b) spraying particles of said liquid anhydrous alltanoic acid into the upper portion of the reaction zone and preventing contact between the liquid anhydrous allzanoic acid particles and the internal surface of the reaction zone to produce a free flowing particulate solid product consisting essentially of said ammonium salt of said liquid anhydrous alkanoic acid.

in especially preferred embodiments of the process of Embodiment A, supra:

(l) The particles of liquid anhydrous alkanoic acid are of a size to produce particles of said free flowing ammonium salt of said liquid anhydrous alkanoic acid which pass a I00 mesh screen.

(2) The liquid anhydrous acid is isobutyric acid or vaicric acid.

(3) The process is operated in a fully continuous manner.

(4) The reaction zone is a jacketed reaction zone having a heat exchange medium circulating through the jacket. Water is a preferred heat exchange medium.

in another preferred embodiment ("Embodiment it) this invention is directed to an improvement in a process for preparing a solid ammonium salt of a liquid anhydrous alltanoic acid having l-l0 carbon atoms per molecule comprising contacting a spray consisting essentially of said liquid anhydrous aikunoic acid with anhydrous ammonia vapor in a first reaction zone having an external surface, an internal surface. a side wall, a top. a bottom, an upper portion, and a lower portion and recovering the resulting solid ammonium salt of said liquid alkanoic acid the improvement comprising:

(a) forming a liquid anhydrous mixture consisting essentially of an anhydrous solution of about 30-60% (more preferably about 40-50%) of the ammonium salt of said liquid anhydrous alltanoic acid dissolved in said liquid anhydrous alkanoic acid by contacting anhydrous ammonia and said liquid anhydrous acid in a second reaction zone; and

(b) filling the first reaction zone with anhydrous ammonia vapor by spraying liquid anhydrous ammonia into the upper portion of said first reaction zone and vaporizing said ammonia therein; and

(c) spraying particles of the liquid anhydrous mixture into the upper portion of the first reaction zone without contact between the liquid anhydrous mixture and the internal surface of the first reaction zone to produce said solid ammonium salt of said liquid alltanoic acid in the form of a free flowing particulate solid.

in especially preferred embodiments of the process as art forth in Embodiment B, supra:

(l) The particles of said liquid anhydrous mixture are of a size that the particles of said solid, free flowing, parliettlate ammonium salt of said liquid anhydrous alkanoic acid pass a I mesh screen.

(1) The liquid anhydrous alltanoic acid is isobutyrtc acid and the salt is ammonium isobutyrate.

(3) The process is operated in a fully continuous manner.

(4) The first reaction zone is a iacketed reaction zone having a heat exchange medium circulating through the acket. Water is an especially preferred heat exchange medium.

(5) The liquid anhydrous alltanoic acid is valeric acid and the salt is ammonium valerttte.

DETAILED DESCRlPTlON OF THE INVENTION Where using the process of this invention it is important tltat the above-mentioned liquid anhydrous ailtanoic acid or the above-mentioned liquid prayed into the reaction zone in such a manner that the spray particles do not contact the side wall of the reaction IUHC internal surface (including the side wall) because such contact will result in the bttild up of a coating of the ammonium salt of the liqttid anhydrous alkrtnoic acid on wall. This will produce product which adheres to the wall and which is neither particulate nor free flowing and which must ultimately be scraped from the wall.

We have found that best results are obtained where the articles of nlltanoic acid spray (or the particles of the above-mentioned liquid anhydrous mixture spray) are of strtit size that the particles of solid anhydrous ammonium salt which forms as the spray particles react with the anhyttt'nns ammonia vapor will pass about a i00 mesh screen. I-urlher where said ttctd (or anhydrous mixture) spray is of such size that the product particles are retained on a ltlO mesh screen the product is impure (i.e., it contains more than 0.2% free (unreactcd) nlkanoic acid).

We have also found that best results are obtained where the liquid anhydrous ammonia is fed into the reaction Tone as a line spray so that the ammonia is promptly vaporized. if droplets of liquid ammonia fall onto the solid frce flowing particulate product (the ammonium salt of the liquid anhydrous alltanoic acid) in the lower portion [or lower section) of the reaction zone the particles of aititi salt are converted into roclt hard spherical noodles for lumps or chunks) which weigh from about 0.5 gto Int) or more.

We have also found that feeding the anhydrous amutunia into the reaction zone as liquid anhydrous amnumia and vaporizing said liquid anhydrous ammonia in the reaction zone (reactor) permits a throughput (conversion per hour) which is five times greater than that attainable where using the same reaction zone and feeding anhydrous ammonia vapor per se (rather than liquid anhydrous ammonia) into said reaction zone.

The stoichiometry of the exothermic reaction resulting in the formation of the ammonium salt of an alltanoic acid in our process is represented by the following equatltlni RCOOH-l-NH RCOONH.

where R is hydrogen or an alltyl group having 1-9 carbon itilllTl.

We have found that in order to obtain a pure product it is necessary to maintain at least a stoichiometrlc quantity of anhydrous ammonia vapor in the reaction zone (an exccts of ammonia does no harm). We prefer to do this by providing an atmosphere of ammonia (at least 90% NH,) in the reaction zone before starting a run and then supplying the ammonia as liquid anhydrous ammonia at a rate which will provide a mole of anhydrous ammonia tu or for every mole of free (unreucted) alkanoic acid t'tnycti into the reaction zone. if insufficient ammonia is anhydrous mixture be I present the product will be contaminated with free (unrcacted) alkanoic acid.

While we prefer to operate our process at about atmospheric pressure tie, with a pressure of about 760 rpm. of mercury absolute in the reaction zone) we have obtained excellent results at pressures ranging from about 500-2000 mm. of mercury absolute.

The process of our invention can be operated as a batch process but it is more convenient to operate tt as a fully continuous process.

Where operating as a batch process a quantity of product is permitted to accumulate in the lower portion of the reaction zone, acid feed and ammonia feed are discontinued, most of the product is removed, and a new run is started. Retaining some product in the reaction zone prevents the escape of appreciable quantities of free (unreacted) ammonia.

Where operating in a continuous manner a quantity of product is permitted to accumulate in the lower portion of the reaction zone, then, while continuing to feed liquid anhydrous ulkttuoic acid and liquid anhydrous ammonia into the reaction zone, prodttct is removed from the reaction zone and recovered at substantiall the same rate that it (said product) is formed. This procedure retains a quantity of free flowing anhydrous particulate product in the lower portion of the reaction zone at all times to prcvent any substantial quantity of unrcrtctcti ammonia front escaping from the reaction zone as product is removed therefrom.

A more comprehensive understanding of ottr invention can be obtained from the following detailed description of a preferred method for operating said process involving the use of apparatus disclosed in the drawing-quid drawing showing a schematic cross section view of a preferred apparatus.

The apparatus comprises a reaction zone (or reactor) shown generally at l in which the product ammonium salt is formed. The pro uct ammonium salt passes via valve 20 (e.g., a gate valve, plug valve, or the like) and line 19 to conveyor means 2! (e.g., a screw conveyor, a belt conveyor, a cup conveyor. or the like) to hugging means 23 from which is passed to a bag or package 24. (the bag is not part of the apparatus.) Motor 22 drives conveyor means 21.

The reaction zone has a side wall 2. a top 3.1: bottom 4. an upper portion 5, and a lower portion 6. We generally prefer to use a jacketed reaction zone. Said jacket is shown at 7. A liquid cooling medium enters the jacket via line 8 and exits the )ttcltct via line 9. Liquid anhydrous ammoni enters the reaction zone via line 10, valve ll, and spray nozzle 12. We generally prefer to feed the ammonia via a hollow cone nozzle. bttt have obtained excellent results with a solid cone nozzle. a fan nozzle, a rotating nozzle. and an impact nozzle. The ammonia which enters as an anhydrous liquid quickly vaporizes in the reaction zone to fill said zone with anhydrous ammonia vapor.

The liquid anhydrous alltanoic acid (or, where using Embodiment B or an embodiment thereunder the liquid anhydrous mixture consisting essentially of an anhydrous solution of the desired ammonium salt of the liquid anhydrous alkanoic acid dissolved in said liquid anhydrous alltanoic acid) enters the reaction zone via line 13. valve 14. and spray nozzle is. The spray nozzle is so oriented that particles of the spray do not come into contact with an inner surface of the reaction zone (we feed the acid or acid mixture into the system in such a manner that all the acid in the acid feed has been converted to the desired ammonium salt before striking any surface within the reaction zone). We prefer to feed the aikanoic acid (or alkanoic acid-containing mixture) into the reaction zone via a hollow cone nozzle but we have obtained excellent results with a solid cone nozzle. a fan nozzle, a rotating nozzle, and an impact nozzle.

Within the lower portion ft of the reaction zone is an agitator (or sctappcr) 16 preferably an anchor type agitutor which is preferably positioned about At-V2 inch l'rom the side Wall 2 and bottom 4 of the reaction zone. Agitator shaft 17 conveys energy from motor 18 to drive agitator 16.

Valve 20 is so operated as to prevent the accumulation of loo mttch product in the reaction zone and at the same time to prevent the escape of appreciable amounts of free ammonia from said zone.

When starting a run we purge the reaction zone with ammonia ttntil the atmosphere within the reaction zone is ttl least about 90% (preferably about 95l00%) ammonia vapor and then spray feeding nlltnnoic acid or the above mentioned liquid alkanoic acid-contacting mixtttre irtto the upper portion of the reaction zone. Liquid anhydrous ammonia is spray led into the upper portion of the reaction zone simultaneously with the acid (supplying a mole of ammonia per mole of free (unreacted) acid]. thereby to maintain an atmosphere of ammonia in the reaction zone.

The reaction between the ammonia and the alkanoic acid is exothermic. We have found that we can operate our process with excellent results when the temperature within the reaction zone is about IOU-23$ F.; however. we prefer to operate within a range of about lfiO-ZOO F. We prefer to control the temperature by passing a cooling medium through the jacket which. as noted supra. surrounds the reaction zone. Temperature control can also be ellccted to some extent by the rate at which we ltll'fll the desired ammonium salt (e.g.. by the rttte :tt illth the reactants are fed into the reaction zone). We prefer to direct the acid spray ttt a point just below the point at which the ammonia enters the reaction zone to insure good contact between the acid and the ammonia. thct'eby to prevent unreacted acid from contacting an internal surface of the reaction zone.

when doing this tve get instant crystallization of the sprayed (or logged) alkanoic acid. The clTect is sonichat like a snow storm and the product is a free flowing. anhydrous, particulate solid consisting essentially of the ammonium salt of the acid.

The instant invention will be better understood by refcrring to the following specific but nonlimiting examples. It is understood that said invention is not limited by these examples which are ollcrcd merely as illustrations; it is also understood that modifications can be made without departing frotn the spirit and scope of the invention.

Example 1 A reaction zone (capacity about 4.000 gallons) of the type shown in the drawing and described supra was purged with ammonia (fed in as liquid anhydrous ammonia and vaporized in the reaction zone) to form an atmosphere therein which analyzed 95% NH- The operation was conducted at atmospheric pressure (760 mm. of mercury absolute).

The exit valve (20 in the drawing) was closed and liquid anhydrous isobutyric was fed into the reaction zone as a fine spray via line 13. valve 14. and acid spray nozzle while continuing to feed liquid anhydrous ammonia into the reaction zone via ammonia feed line It). ammonia pressure control valve 11, and ammonia spray nozzle 12. The isobulyric acid feed rate was 440 pounds (5 pound molccttlar weights) per hour and the ammonia feed rate was 85 pounds (5 pound molecular weights) per hour. The isobutyric acid entering the reaction zone had a temperature of 2t C. and the ammonia entering said zone had a temperature of 23 C. lsobutyric acid nozzle 15 was so oriented that the liquid anhydrous isobutyric acid spray did not contact the internal surface of the reaction zone.

Drive motor 18 was started (when the acid feed was begun) to rotttte agitator 16. After a layer of product solid. free flowing. particulate, anhydrous ammonium isobutyrute had accumulated in lower portion (or section) 6 of the reaction zone motor 22 was started and valve 20 was partially opened to permit the salt (the aforesaid ammonium isobutyratc) to exit from reaction zone 1 via valve 20 and line 19 at substantially the same rate it (said salt) was formed. The salt was conveyed by conveyor 21 to packaging (or bagging means) 23 and then bagged in 50 pound bags.

A representative sample of the bagged product was taken and analyzed. it was found to be pure anhydrous. solid free flowing. particulate. anhydrous ammonium isobtttyrate analyzing 99.5% ammonium isobutyrate. 0.1)? free (unreucted) isobutyric acid. and 0.3% H 0. said product passed a I00 mesh U.S. standard screen.

During the rtrn which lasted for 8 hours cooling water (entering temperature 22 C.) was passed through jacket 7 at a rate to keep the temperature within the reaction zone within a range of t-l85 F. (ca. tt0-85 C).

The temperature at which the isobutyric acid is fed into the reaction zone can be varied over a wide range and is not critical. Excellent results were obtained when the liquid anhydrous isobutyric acid was fed at 3 23 C.. and 40 C. Excellent results were also obtained at temperatures below 3 C. and rtbove 40 C.

The liquid anhydrous ammonia is generally fed at its storage temperature which varies from about 5 C. to 30 C. depending on the season. However excellent results have been Obtained at temperatures below 5 C. and ttbove 30 C.

A number of rttns were made using the general procedure of Example l but maintaining the temperature within the reaction zone at: (a) 100-125" Fm, (h) tittl60 F.'. (c) l65-l80" F.; and (d) l-200 F. in each instance high quality, pure, solid. anhydrous. free fluirtg ammonium isobutyrnte passing a I00 mesh screen and analyzing at least 99.5% ammonium isobutyrute and not more than 0.2% free (unreactcd) isobutyric acid and up to 0.3% H 0 was obtained.

in another series of rttns the general procedure oi Example 1 was repeated; however. in these runs the istt butyric acid was replaced with anhydrous; (a) formicacid; (b) acetic acid; (c) propionic acid; (tt) norrttnl butyric acid was replaced with anhydrous: (a) formic each instance the liquid anhydrous acid was fed into the reaction zone at a rate of 5 pound moles per hour and the ammonia was fed into said zone at a rate of 5 pounds per hour.

In each instance the product was a pure. solid. anhydrous, free flowing particulate ammonium salt of the acid used-said salt passing :1 I00 mcsh screen and analyzing at least 99.5% ammonium salt of the acid used. not more than 0.2% free acid and up to 0.3% H 0. Sintila results are obtained with C C C and C alkanoic acids (i.e.. alltanoic acids having 7 8. 9, and t0 Carbon atoms).

Two additional runs were made using the general procedure of Example 1. However. in one instance the ressure within the reaction zone was 500 mm. of mercury absolute and in the other the pressure was 2000 mm. ot' mercury absolute. The results of the run and products obtained in these runs were indistinguishable from that oh rained in Example t.

Example 2 The general procedure of Example 1 was repeated; however. in this instance the procedure was modified by rcplacing the isobutyric acid led into the reaction zone used in Example 1 (a first reaction zone) with a liquid arthydt'ous mixture (:1 solution of anhydrous ammonium isobutyrate dissolved in liquid anhydrous isobutyric acid). Said solution analyzed 60% isobutyric acid and 40% ammonium isobutyrate. Said solution was prepared by reacting ammonia and isobutyric acid in a reactor (a second reaction zone) having an agitator and heat e. change coils (if desired a jacketed reactor can be used). Liquid anhydrous isobutyric acid was placed in the second reaction zone and liquid ammonia was fed into sattl second reaction zone while agitating the acid (and the resulting solution) in said zone. A heat exchange medium (e.g.. water. or the like) was circulated through the cooling coils to cool the resulting solution to the desired temperature range (e.g.. 100430 C. which has been found to give excellent results).

The temperature of the aforesaid anhydrous mixture (said anhydrous solution of ammonium isobutyrate in anhydrous isobutyric acid) was adjusted to about ll F. by passing said anhydrous mixture through a heat exchanger. The aforesaid anhydrous mixture was then led into the reaction zone used in Example l (the first reaction zone) at a temperature of about 110' F. and at a rate to provide pound moles of isobutyric acid per hour while ammonia was fed into said first reaction zone at a rate to provide 5 pound moles of ammonia per hour. The ammonia feed was supplied an anhydrous liquid ammonia at 25 C. The product of this run was indistinguishable from that of Example 1.

Where runs are made using the general procedure of Example 2 except that: (a) the anhydrous isobutyric acid is replaced with a second tliitlttlOiC acid having l-lt) carbon atoms; and (b) the anhydrous solution of antmonium isobutyrate in isobutyric is replaced with an anhydrous solution of the ammonium salt of the second alkanoic acid dissolved in the second alkanoic acid, the results are as in Example 2 except that the final product is the free flowing particulate ammonium salt of the second allutnoic acid. The final product passes a iOtl mesh screen and analyzes about 0.2% said alkanoic acid (as free acid) and not more than 0.3% H;Othe remainder (99.5%) is said ammonium salt of said second aikanoic acid.

As used herein the term "percent means parts per hundred and "parts" means parts by weight.

The term "mesh" as applied to particle size means U.S. standard.

The term "conversion" means one pass yield.

An anhydrous or substantially anhydrous ammonium salt of an alkanoic acid having l-lO carbon atoms is an ammonium salt of such acid analyzing less than about 0.4% H 0.

Ammonium salts of alltanoic acids prepared according to the process of our invention are useful for retarding or preventing the growth of mildew in silage and the like. It has been found that little or no mildew forms on silage prepared and stored in either an underground (trench type) silo or an aboveground (tower type) silo if such ammonium salt (or a mixture of such ammonium stilts) is applied to the silage according to the general procedure of U.S. patent application Ser. No. 76,224, tiled Sept. 28, 1970 (Lepore et al.) which is assigned to W. R. Grace 8: Co.

Ammonium salts of alkanolc acids having l-lO carbon atoms prepared according to the method of this invention have been used with excellent results to prevent mildew from growing on moist seeds (which will be planted). Such salt is applied at the moist seeds at a rate to provide about 0.25-2 pounds of salt per [00 pounds of moist seeds. When applied at this rate the salt does not laterlcre with the germination of the seeds and actually supplies some nitrogen fertilizer.

We claim:

l. in a process for preparing a solid ammonium salt of a liquid anhydrous alltanoic acid having l-lO carbon atoms per molecule comprising contacting a spray of said liquid anhydrous alkanoic acid with anhydrous ammonia vapor in a reaction zone having an internal surface, an upper portion, and a lower portion and recovering the resulting solid ammonium salt of said liquid alkanoic acid, the improvement comprising; filling the reaction zone with at least a stoichiometrie amount of anhydrous ammonia vapor by vaporizing liquid anhydrous ammonia in the upper portion thereof and spraying particles of said liquid anhydrous alkanoic acid into the upper portion of the reaction zone while maintaining the temperature within said zone at -235 F. without contact between the liquid anhydrous aikanoic acid particles and the internal surface of the reaction zone to produce a free ilo" ng particulate solid product consisting essentially of said ammonium salt of said liquid anhydrous alkanole acid.

2. The process of claim 1 in which the alltanoic acid has 4 or 5 carbon atoms.

3. The process of claim 1 in which the particles of liquid anhydrous alkanoic acid are of a size to roduce particles of said free flowing ammonium salt of said liquid anhydrous alkanoic acid which pass a 100 mesh screen and the process is operated in a fully continuous manner.

4. The process of claim I in which the liquid anhydrous alltanoic acid is isobutyric acid or valcric acid.

5. la a process for preparing a solid ammonium salt of a liquid anhydrous allianoic acid having t-lO carbon atoms per molecule comprising contacting a spray of said liquid anhydrous ulkanoic acid with anhydrous naimonia vapor in a reaction zone having an external surface, an internal surface, a side wall, a top, a bottom, an upper portion, and a lower portion and recovering lilt: resulting solid ammonium salt of said liquid alkanoic acid, the improvement comprising:

(a) filling the reaction zone with anhydrous ammonia vapor by feeding at least a stoichiomctric amount of liqttid anhydrous ammonia into the upper portion of the reaction zone and vaporizing said ammonia therein; and

(b) spraying particles of said liquid anhydrous aikanoie acid into the upper portion of the reaction zone while maintaining the temperature within said zone at l00-235' F. and preventing contact between the liquid anhydrous aikanoic acid particles and the internal surface of the reaction zone to roduce a free flowing particulate solid product consisting cssentially of said ammonium salt of said liquid anhydrous alkanoic acid.

6. The process of claim 5 in which the particles of liquid anhydrous alltanoic acid are of a size to product: particles of said free flowing ammonium salt of said liquid anhydrous alltanoic acid which pass a 100 mesh screen.

7. The process of claim 5 in which the liquid anhydrous slkanoic acid is isobutyric acid or valeric acid.

8. The process of claim 5 wherein the process is operated in a fully continuous manner.

9. The process of claim 5 in which the reaction zone is a jacketed reaction zone having a heat exchange medium circulating through the jacket.

10. in a process for preparing a solid ammonium salt of a liquid anhydrous alltanoic acid having l-lO carbon atoms per molecule comprising contacting a spray consisting essentially of said liquid anhydrous alltanoic acid with anhydrous ammonia vapor in a first reaction zone having an external surface, an internal surface, a side wall. a top, a bottom, an upper portion, and a lower portion and recovering the resulting solid ammonium salt of said liquid alltanoic acid, the improvement comprising;

(a) forming a liquid anhydrous mixture consisting essentially of an anhydrous solution of about 45- 55% of the ammonium salt of said liquid anhydrous alkanoic acid dissolved in said liquid anhydrous alkanoic acid by contacting anhydrous ammonia and said liquid anhydrous alltanoic acid in a second reaction zone;

(b) filling the first reaction zone with anhydrous ammonia vapor by feeding at least a stoichiometric amount of liquid anhydrous ammonia into the upper portion of said first reaction zone and vaporizing said ammonia therein; and

(c) spraying particles of said liquid anhydrous mixturn into the upper portion of the first reaction zone while maintaining the temperature within said first reaction zone at l0t)-23S' F. without contact between said liquid anhydrous mixture and the internal surface of the reaction zone to produce said solid ammonium salt of said liquid alkanoic acid in the form of a free flowing particulate solid consisting essentially of said ammonium salt 1!. The process of claim 10 in which the particles of said liquid anhydrous mixture are of a size that the particles of said solid, free flowing, particulate ammonium salt of said liquid anhydrous alkanoic acid pass a 100 mesh screen.

12. The process of claim 10 in which the liquid anhydrous alkanoic acid is isobutyric and the salt is ammonium isobutyrate.

13. The process of claim 10 in which the process is operated in a fully continuous manner.

14. The process of claim 10 in which the first reaction zone is a jacketed reaction zone having a heat cxchunpc medium circulating through the jacket.

15. The process of claim 10 in which the alkanoic acid is valeric acid and the salt is ammonium valerate.

References Cited UNITED STATES PATENTS 3,123,632 3/1964 Katschmann 260-540 OTHER REFERENCES Zufianli, J. A. C. 5.. 1941, 63: 3123-24.

VIVIAN GARNER, Primary Examiner US. Cl. X.R. 260404. 541. 542 

